Look up RunAPI pricing for Luma model line. Optionally provide model and endpoint to get cost details.
Look up RunAPI pricing for the luma model line.
| Name | Required | Description | Default |
|---|---|---|---|
| model | No | Model slug. Defaults to the line's primary model. | |
| action | No | Endpoint name. Defaults to the endpoint that offers the model. |
Changes observed during successful MCP inspections.
v0.3.0Input schema / properties / action / enumRemoved value: -[
- "modify_video"
-]v0.2.0Input schema / additionalPropertiesRemoved value: -falseInput schema / properties / model / enumRemoved value: -[
- "luma-modify-video"
-]v0.1.4Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden. It implies a read-only lookup but never states that it is non-mutating, whether auth is required, whether results are cached or subject to rate limits, or what the returned pricing represents (per-token, per-call, currency).
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
A single front-loaded sentence with no filler; it is efficient, though arguably too terse for a tool with two parameters and no annotations to lean on.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
There is no output schema and no annotations, so the description is the only source of context, and it omits what the returned pricing data looks like and under what conditions it applies. For a simple lookup this is minimally adequate but leaves real gaps.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100% and both parameters are optional with documented defaults, so the baseline is 3. The description's mention of 'the luma model line' loosely hints at the model parameter but adds no syntax, format, or default behavior beyond what the schema already documents.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb (look up) and resource (RunAPI pricing), and scopes it to the luma model line, which separates it from the unrelated siblings get_task and login. However, the fixed scope to 'the luma model line' sits awkwardly with a schema that accepts an arbitrary model slug, so the intended breadth of the tool is slightly ambiguous.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
No guidance on when to call this versus alternatives, no preconditions, and no mention that pricing lookups may require authentication (a sibling 'login' tool exists). The agent is left to infer all usage context.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.